Method of reproducing images from opaque surfaces



Jan. 8, 1946. P. TABER ET AL, 2,392,343

METHOD OF REPRODUCING IMAGES FROM OPAQUE SURFACES Filed Sept. 3, 1940 lllllll llllllll l l .1 ll

WWW

INVENTORS. Pf? [Z40 fiber and Ldwence 144' 16/2 Dzmen ATTORNEY.

Patented Jan. 8,1946

METHOD'OF REPRODUCING IMAGES FROM OPAQUE SURFACES Philip Taber and Lawren Diego, Calif.,

syl

ce W. Van Dusen, San assignors to D. L. Ward Company, Philadelphia, Pa., a corporation of Penn- Application September 3, 1940, Serial No. 355,124

3 Claims.

Our invention relates to a method of reproducing images from opaque or similar surfaces, more particularly for use in reproducing images of drawings, or the like, which are executed or posi-.,

tioned on rigid opaque or similar surfaced plates, table tops or the like and the objects of our invention are:

-First, to provide a method of this class which produces positive reproduction images which are very accurate in relation with the original image from which said reproduction images are developed:

Second, to provide a method of this class in which the original opaque image plate is placed face to face with a sensitized plate, the sensitized surface of said sensitized sheet being in flat direct contact relation with the image side of said original image plate whereby an impression of said image is reflectively projected on said sensitized sheet by means of light projected through said sensitized sheet toward said image on said opaque image plate;

Third, to provide a method of this class which promotes the development of images on sensitized surfaces which are accurate and not subject to the natural shrinkage or expansion of the sensitized material during the development of the image on said sensitized material;

Fourth, to provide a method of this class in which the developed image retaining surface of the negative is placed in direct face to face contact relation with a sensitized surface of a positive image receiving plate for extremely accurate projection of the image from said negative to the sensitized surface of said positive image receiving plate;

Fifth, to provide a method of this class in which the sensitized image retaining surface of the positive reproduction is maintained in fixed relation with a rigid plate member whereby the development of said sensitized surface does not cause shrinkage of the features of said image retained on said sensitized surface providing extreme accuracy in the reproduction of mechanical drawing or other images;

Sixth, to provide a method of this class in which the impression bearing surfaces and impression receiving surfaces are in face to face contact relation in the projection of images providing for very accurate nnpression and development of both the negative andthe positive image reproduction; and

Seventh, to provide a method of this class which is very simple and economical to use, eflicient and which saves time and effort duction of various images.

With these and other objects in view as will appear hereinafter, our invention consists of the certain novel methods of reproducing images from opaque surfaces as will be hereinafter described in detail and particularly set forth in the appended claims, reference being had to the accompanying drawing which forms a part of this application in which:

Figure 1 is a sectional view showing part of the equipment used in carrying out our method; namely, an original image retaining plate in face to face contact relation with a sensitized negative plate and Fig. 2 is a sectional, view of part of the equipment used in carrying out our process; namely, a developed negative plate in face to face contact relation with a sensitized reproduction plate.

in the accurate reproso The original image retaining plate I, sensitized g5 ably a rigid flat plate member, such as plywood,

negative plate 2 and the sensitized reproduction plate 3 constitute the principal equipment preferred to be used in carrying out our method.

The original image retaining plate I is preferglass or the like, which is unaffected by conditions which would normally cause undue shrinkage or expansion of a conventional drawing paper, tracing cloth, or other yieldable subject matter. This original image retaining plate I may be constructed of .a plywood plate member with a drawing sheet of conventional drawingpaper cemented thereon whereby the drawing sheet is held in rigid accurate relation with the comparatively rigid plate member I. This original image retaining plate I may be a table top or other rigid member arranged to retain an image on its one surface Ia, as shown best in Fig. 1 of the drawing. A drawing may be directly executed on the surface la or other images of printed matter, plctur es or the like may be secured thereon by means of cement so that the image of the particular object on the surface la is maintained in rigid accurate relation during various climatic conditions and various other changes which take place while the image is being fixed or executed on the surface la. The sensitized negative plate 2 is a flat plate member and is translucent, being made of glass or other similar material. This sensitized negative plate 2 is provided with a sensitized surface on its one side designated 2a. This sensitized surface may be of a conventional sensitized paper cemented on the one side of the plate member '2 or this sensitized surface to may be applied in paint like form employing a conventional sensitized surface material.

The sensitized reproduction plate 3 is a flat rigid plate member which may be either translucent or opaque material. This sensitized reproduction plate 3 is provided with a sensitized surface 3a on its one side which sensitized surface may be of the conventional sensitized surface material or may be constructed of conven tional sensitized paper cemented to the plate member 3. This sensitized reproduction plate 3 may be made of plywood, glass or other suitable flat, rigid material and when developed this sensitized reproduction plate bears upon its face a positive reproduction ofthe image positioned on the surface la. of the original image retaining plate I. when developed, as just described, this sensitized reproduction plate 3 is ready for use for any purpose which a positive reproduction may be used, such as shop use in the case of mechanical drawings where the mechanic desires an accurate rigidly maintained image for use in comparison of various parts being constructed in accordance with the image on the developed sensitized reproduction plate 3.

Our method in connection with the use of the hereinhefore described equipment is as follows:

An image of any object desired is executed or positioned in connection with the surface in of the original image retaining plate I and the sensitized negative plate 2 is placed in face to face contact relation with the original image retaining plate i having the sensitized surface of the sensitized negative plate 2 in fiat direct contact relation with the image on the surface to of the original image retaining plate i. The light is then projected through the translucent sensitized negative plate, as indicated by arrows in Fig. 1 of the drawing. The opaque original image retaining plate i with the image thereon causes a reflective projection of the image thereon to the sensitized surface 2:; of the sensitized negative plate 2 impressing upon the said sensitized surface an accurate negative reproduction of the image of the surface in of the original image retaining plate L After the sensitized negative plate 2 has been exposed to the image on the original image retaining plate I, as hereinbefore described, the sensitized surface 2d of the negative plate 2 is developed in the conventional manner while in connection with the rigid plate memher. Then the developed negative plate 2 is that the reproduction may be used by mechanics in the shop for the laying out of various parts.

It will be here noted that in the taking of the impression from the image retaining plate onto the sensitized negative plate that the sensitized surface and the image retaining surface is in direct contact relation making for extreme ac-.

curacy, there being no space between the sensitized surface and the image on the original image retaining plate, there' can be no angular deflection of the image from the original imageretaming surface and the sensitized surface of the negative. Likewise inthe reproduction of the image from the developed negative plate to the sensitized reproduction plate, both sensitized sur- "faces are placed in direct face to face contact relation with each other so that inaccuracy in the final reproduction is avoided in projection of the image from the developed negative to-the positive reproduction plate.

Though we have shown and described a particular equipment and methods of reproducing images from opaque surfaces, we do not wish to be limited to this particular equipment, nor to the methods disclosed, but desire to include in the scope of our invention the methods substantially as set forth in the appended claims.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. The herein described method of reproducing images from plate surfaces consisting in preparing an image on one image retaining surface of a rigid plate member which is immune to longitudinal and transverse dimensional variations due to changes in atmospheric moisture, then preparing a sensitized surface on a rigid light transmitting plate member, then placing said image retaining surface and said sensitized 40 surface in face to face contact relation with each placed in face to face contact relation with the sensitized reproduction plate 3, the sensitized surfaces of both the negative plate 2 and the sensitized reproduction plate 3 being in fiat contact relation with each other. Light is then pro-' jected, as indicated by'arrows, through the developed negative plate 2 projecting an image from the developed negative plate 2 onto the sensitized surface 3a of the reproduction plate 3.

This image projected onto the sensitized surface v original image of the surface to and this reproduction is ready for use as desired; In cases where the reproduction is of a mechanical drawing or the like, the rigidity of the plate 3 maintains the drawing and all the features thereof in other, then exposing said sensitized surface to said image by directing light through said light transmitting plate member toward said image on said plate member, then developing said sensitized surface on said light transmitting plate member, then reparing a rigid positive image receiving reproduction plate member with a sensitized surface thereon, thenplacing said developed sensitized surface of said light transmitting plate member in face to face contactrelation with said sensitized surface of said positive image receiving reproduction plate member, and then directing light through said light transmitting plate member projecting the image thereon to said sensitized. surface of said positive image receiving reproduction plate member and developing said positive image, the material ofthe images from plate surfaces consisting in preparing an image on one image retaining surface of a rigid plate member which'is immune to longitudinal and transverse dimensional variations due to changes in atmospheric moisture, then preparing a sensitized surface on a rigid light transmitting plate member, then placing said image retaining surface and said sensitized surface in face to face contact relation with each accurate proportionate relation to each otherso other, then exposing said sensitized surface to said image by directing light through said light transmitting plate member toward said image veloped sensitized surface of said light trans-' mitting plate member in face to face contact relation with said sensitized surface of said positive image receiving reproduction plate member, then directing light through said light transmitting plate member projecting the image thereon to said sensitized surface of said positive image receiving reproduction plate member, then developing the positive image on said positive image receiving reproduction plate member, the material of the light transmitting plate member and the reproduction plate member being such as to maintain the respective sensitive surfaces thereof immune to longitudinal dimensional variations throughout the developing steps and immune also to longitudinal and transverse dimensional variations due to changes in atmospheric moisture.

3. The herein described method of reproducing images from plate surfaces consisting in preparing an original image retaining plate with an image on one surface thereof, said image retaining plate being immune to longitudinal and transverse dimensional variations due to changes in atmospheric moisture, then preparing a negative with a sensitized surface thereon, then placing the sensitized surface of said negative in face to face contact relation with said image on said original image retaining plate, then exposing said negative to said image, then developing said negative, then preparing a sensitized reproduction plate with a sensitized surface thereon, then placing the developed negative in face to face contact relation with said sensitized reproduction plate whereby the image retaining surface of said negative plate is in direct contact with the sensitized surface of said sensitized reproduction plate, then projecting by light the image from the developed negative to said sensitized reproduction plate and then developing the image on said sensitized reproduction plate, the material of the light transmitting plate member and the reproduction plate member being such as to maintain the respective sensitive surfaces thereof immune to longitudinal dimensional variations throughout the developing steps and immune also to longitudinal and transverse dimensional variations due to changes in atmospheric moisture. PHILIP TABER.

LAWRENCE W. VAN DUSEN. 

